Difficulty has been encountered in operating electronic equipment in an environment containing airborne pollutants. More specifically, certain equipment such as a magnetic storage disk read/record unit, may encounter reliability and life problems in certain environments such as a manufacturing plant, for example, because of the necessity for providing an opening in the equipment housing for loading and removal or replacement of magnetic storage disks which may contain data base information, programs, etc. The problem is aggravated in some instances by the need to use equipment cooling fans to dissipate excessive heat generated by operation of the equipment. The air drawn into the equipment through the opening for the disk by the fan may contain pollutants which will cause damage to components such as the read/write head and the storage media. Closing of the disk opening by a movable cover permits an arrangement in which air circulation is directed through another opening provided with a filter which is capable of removing most of the pollutants.
It is known to provide a cover for magnetic disk units which form a part of a business terminal, as shown, for example, in copending U.S. patent application Ser. No. 749,358, filed June 27, 1985 now U.S. Pat. No. 4,636,781, issued Jan. 13, 1987, inventors David C. Wills et al., assigned to the assignee of the present application.